Since then, Katy has been relatively quiet about Taylor, only throwing the occasional subtle shade on Twitter, but has now suggested that she’d be ready to leave the past in the past and even collaborate with the ‘Shake It Off’ singer on a future project… but only if the latter swallows her pride and apologises first.

Over the weekend, Katy had a bit of a Q&A session with her fans, with one posing the question: “Will you collab with Taylor Swift?”

We have a feeling that’s a duet we could be waiting a loooooong time for…

Kevin Mazur via Getty Images
You know, they used to be mad love

When Katy was first suggested in the press as the subject of ‘Bad Blood’ (which, incidentally, has never actually been confirmed by Taylor), she compared her to ‘Mean Girls’ Queen Bee Regina George, tweeting at the time: “Beware of the Regina George in sheep’s clothing.”